Bug 43839

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User-Agent: Mozilla/4.0 (compatible; MSIE 5.5; Windows NT 5.0)

Description of problem:
When mounting a samba volume, files that already contains data can not be 
truncated. Problem occurs with kernel version 2.2.19-7.0.1. With kernel 
version 2.2.17-14 the problem does not exist. I have not tried with the 
latest 2.4 kernel yet.

How reproducible:
Always

Steps to Reproduce:
1.Run the included program on a system with kernel 2.2.19-7.0.1.
2.As command line argument specify a file on a samba mounted volume.
3.Make sure that the file already contains some data like the alphabet for 
example.
	

Actual Results:  ftruncate: Permission denied

Expected Results:  No error message

Additional info:

int main(int argc, char *argv[])
{
  int fd, i;
  char buf[20];
  
  if (argc != 2)
    {
      fprintf(stderr, "usage: %s file\n", argv[0]);
      return 1;
    }
  if ((fd = open(argv[1], O_RDWR|O_CREAT, S_IRUSR|S_IWUSR)) < 0)
    {
      perror("open");
      return 1;
    }
  if (read(fd, buf, sizeof buf) == -1)
    {
      perror("read");
      return 1;
    }
  if (ftruncate(fd, 0) == -1)
    {
      perror("ftruncate");
      return 1;
    }
  return 0;
}